Floor selector for an elevator control system



FLOOR SELECTOR FOR AN ELEVATOR CONTROL SYSTEM Filed July 31, 1962 C.SAVAGE 8 Sheets-Sheet 1 Dec. 8, 1964 /7$U ,vso

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INVENTOR Conwell Savage U D S I. 3 3 x M ww 44 .m U F D B 5 -r U U U 0 DD D D 0 5 W 5 5 0 w 0 2 l l I 2 wnuesses ATTORNEY Dec. 8, 1964 C. SAVAGEFLOOR SELECTOR FOR AN ELEVATOR CONTROL SYSTEM Filed July 31, 1962 8Sheets-Sheet 2 c. SAVAGE 3,160,232

SELECTOR FOR AN ELEVATOR CONTRCL SYSTEM Dec. 8, 1964 FLOOR 8Sheets-Sheet 5 Filed July 31, 1962 FLOOR SELECTOR FOR AN ELEVATORCONTROL SYSTEM Filed July 51, 1962 C. SAVAGE Dec. 8, 1964 8 Sheets-Sheet4 Dec. 8, 1964 c. SAVAGE 3,160,232

FLOOR SELECTOR FOR AN ELEVATOR CONTRCL. SYSTEM Filed July 51, 1962 8Sheets-Sheet 5 49A llIl|lIlH-49 Dec. 8, 1964 c. SAVAGE 3,160,232

FLOOR SELECTOR FOR AN ELEVATOR CONTROL SYSTEM Filed July 51, 1962 8SheetsSheet 6 Dec. 8, 1964 c. SAVAGE 3,160,232

FLOOR SELECTOR FOR AN ELEVATOR CONTROL SYSTEM Filed July 51, 1962 8Sheets-Sheet 7 0-00 -0 49A(2]-I 33D DPL L V ZDRN 53(2)'l 2LAD 53(2)-2 ODown Lantern 4UR 4URN 49(4)-l2 Fig.l2.

Dec. 8, 1964 c. SAVAGE 3, 6

FLOOR SELECTOR FOR AN ELEVATOR CONTROL SYSTEM Filed July 31, 1962 8Sheets-Sheet 8 PMI Voltage 263 Regulator Fig.l3.

United States Patent Oftice Patented Dec. is, lQb' -l 3,36%,232 FLUGRSELECEUR FGR AN EEEVATQR tCttlNllltlL dYSTlllsd Conwell havage, NewYork, N.Y., assignor to Westinghouse Electric Qorporation, EastPittsburgh, Pin, a corporation oi Pennsylvania Filed Italy 31, T1952,Ser. No. 213,738 19 Claims. (Cl. Ebb-29) This invention relates toelevator systems, and it has particular relation to mechanisms andsystems for controlling the starting and stopping of elevator cars.

Although the invention may be employed in whole or in part with varioustypes of elevator systems, it is can ticularly suitable for elevatorsystems wherein an elevator car stops automatically in response to callsfor service. The calls for service may be registered by means of carcall buttons positioned within the elevator car or by means of floorcall buttons operated by waiting passengers at the various floors servedby the elevator car.

he elevator system may be of the automatic type wherein an elevator carstarts automatically in response to registration of a call for service.However, the invention also is suitable for an attendant-operatedelevator system wherein an attendant in the elevator car must performsome function in order to permit the car to start for the purpose ofanswering a call for service.

The invention is directed particularly to a tloor selector for anelevator system. Although the door selector may control the entireslowdown and stopping o eration of an elevator car, preferably the doorselector is employed for controlling the preliminary or initial slowdownof the car. in a preferred embodiment of a system employing the doorselector, deceleration of the elevator car as it completes its approachto each of the floors, the stopping point for each of the floors andleveling operations are controlled by highly accurate equipment loomedon the elevator car and in the hoistway within which the ca operates.

The door selector includes a pair of carriage units which lOVE inopposite directions. Conveniently, one of the carriage units, termed anup carriage unit, may be employed primarily for control operationsrequired during up travel of the elevator car. The remaining or downcarriage unit may be employed orirnarily for control oprations requiredfor down travel of the car.

Each of the carriage units comprises a synchronous carriage, which ismoved in accordance with movement of the elevator car, and an advance orlead carriage, which is connected to the synchronous carriage through alostmotion co oling. Preferably, the two synchronous carriages areconnected in a flexible loop. Similarly, the advance carriagespreferably are associated in a flexible loop. Drive units for the twoflexible loops then may be associated with a common supportingstructure. After each stop of the elevator car, the synchronouscarriages preferably are reset or accurately positioned with respect tothe advance carriages.

in accordance with the invention, each or" the carriage units is mountedon a support in the form of only a single independent guide element orrail. Each of the aforementioned advance ca rrlages comprises a platewhich is parallel to its associated rail. Mounted on the plate are aplurality of rollers which cooperate with grooves in opposite sides ofthe rail for guiding the carriage unit. Each synchronous carriage alsocomprises a plate which is parallel to its associated advance carriageplate. This plate is supported and guided for movement by a plurality ofrollers mounted on the advance carriage plate.

Floor top points are determined by simple and effective blocks or clampswhich preferably are secured to the same rails employed for guiding thecarriage units.

The clamps are positioned accurately by means of cooperating clamp legsand rail flanges or shoulders. The same clamps preferably are employedfor supporting switches associated with eacn of the doors served by theelevator car. Such switches are operated by cams secured to the advancecarriages. inasmuch as the clamps are secured to the same rails employedfor guiding the carriage units, correct alignment between the carriageunits and the components secured to the clamps is assured. Each of theclamps also may include a cam which operates a control switch carried bythe associated advance carriage.

in a floor selector constructed in accordance with the invention, a sliht camber or twist of a carriage unit guide rail does not adverselyaffect operation of the selector. in addition, the switches supported bythe clamps secured to a guide rail will not have varying operatingpoints as a result of shifting of the horizontal position of theassociated carriage unit.

in a preferred embodiment of the invention, the synchronous carriagescarry no switches. Each synchronous carriage has a. cam for operatingswitches secured to a plate "canted on the associated advance carriage.

D .ably, initial deceleration of the elevator car also is reg ed bycontrol units having relatively movable parts mounted on the advance andsynchronous carriages.

Thus, each carriage unit may include a solenoid control unit having acoil mounted on the advance carriage plate and magnetic armature or corewhich is mounted on the associated synchronous carriage plate.Consequently, the impedance of the coil varies in response to relativemovement of the advance and synchronous carriages as a result ofcorresponding relative movement of the coil and its armature. I

it is, therefore, a first object of the invention to provide an improvedfloor selector for controlling oceration of an elevator car.

it is a second object of the invention to provide an improved elevatorfloor selector comprising a pair of carriage units, each carriage unitbeing mounted for movement along a support comprising only a singleindependent guide rail.

it is a third object of the invention to provide a floor selector asspecified in the preceding object, wherein floorstop points aredetermined by clamps secured to sucl guide rail.

it is a fourth object of the invention to provide an elevator floorselector ha ing a carriage unit including an advance and a synchronouscarriage which are coupled to each other through a lost-motion couplingand in which the advance and synchronous carriages comprise parallelplates.

it is a fifth object or" the invention to provide an elevator iloorselector as define 'n the preceding paragraph, wherein the synchronouscarriage operates switches secured to a plate parallel to and mounted onthe advance carriage.

it is a sixth object of the invention to provide a floor selector asdefined in the fourth object, in which the ad- Vance carriage plate ismounted by means of rollers for mover parallel to a single independentguide rail and the synchronous carriage is supported and guided formovement on rollers mounted on the advance carriage.

Other objects of the invention will be apparent from the followingdescrigtion taken in conjunction with the accompanying drawings, inwhich;

FiG-URE 1 is a schematic view with parts shown in elevation and parts incross-section of an elevator system. embodying the invention;

FIG. 2 is a view in front elevation with parts broken away of a floorselector suitable for the system of FIG. 1;

FIG. 3 is a view in side elevation with parts broken away of the doorselector illustrated in FIG. 2;

FIG. 4 is a view in front elevation of a carriage unit suitable for thefloor selector of FIG. 2;

FIG. 5 is a view with parts broken away and parts not shown of a portionof the carriage unit illustrated in FIG. 4;

FIG. 6 is an exploded isometric View of the carriage unit shown in FIG.4;

FIG. 7 is a view taken along the line VII-VII of FIG. 2;

FIG. 8 is a view taken along the line VIII-VIH of FIG. 4;

FIG. 9 is an isometric view with parts broken away and parts not shownillustrating the association of a floor unit, a carriage unit rail andcertain portions of a carriage unit;

FIG. 10 is an isometric view with parts broken away and parts not shownillustrating a further association of the components illustrated in FIG.9;

FIG. 11 is an enlarged isometric view of a portion of the carriage unitillustrated in FIG. 4;

FIGS. 12 and 13 are schematic views with circuits illustrated instraight line form showing control circuits suitable for the elevatorsystem of FIG. 1; and

FIG. 14 is a diagrammatic view showing conditions of electrical switchesin the system of FIG. 1.

GENERAL SYSTEM Although the invention may be employed in various typesof elevator control systems, the control system herein described issimilar to that disclosed in the Oplinger Patent 2,874,806. Thus, FIGS.1, l2 and 13 of the present application respectively are based on FIGS.1, 4A and 4 of the aforesaid Oplinger patent, additions being indicatedin the present FIG. 12 by extra-heavy lines.

Referring to FIG. 1, an elevator motor l is secured to the upper surfaceof a floor 3 which may be located in the penthouse of a building beingserved by the elevator system. The motor 1 has a traction sheave 5secured to its shaft, and an elevator brake '7 is associated with theelevator motor and the traction sheave in a conventional manner.

As will be pointed out below, the brake 7 is spring applied to hold thetraction sheave 5 stationary and is released in response to energizationof a solenoid. A secondary or idler sheave 9 my be secured to the lowersurface of the penthouse floor 3. A control unit It) is operated by theshaft of the motor 1'. This control unit is employed in controlling thespeed of the motor 1 and will be discussed below.

An elevator car 11 is mounted for movement in a hoistway 13 to serve thevarious floors of the building associated therewith. The elevator car isconnected to a counterweight 15 by means of one or more ropes or cables17 which pass around the traction sheave 5 and the secondary sheave 9 ina conventional manner.

At each floor served by the elevator car, a hoistway or floor door 19 isprovided. In addition, the elevator car has a gate 21 which registerswith the hoistway door at any floor at which the elevator car isstopped. The doors and the gate may be of conventional construction andmay be operated automatically in any conventional way. However, forpresent purposes, it will be assumed that the gate and doors are openedand closed by an elevator car attendant.

In order to register calls for floors desired by passengers traveling inthe elevator car, a plurality of car call push buttons 1C through 9C areprovided. It is assumed that the building serviced by the elevator carhas 9 floors requiring service. The car also contains an up push buttonUPB and a down push button DPB which are operated by the car attendantin order to condition the elevator car for up travel or down travel,respectively.

As is illustrated in FIG. 1, an up push button 2U is provided at thesecond door for operation by a person desiring transportation in the updirection. A similar push button would be provided at each of the floorsfrom which a person may desire to travel in the up direction.Hereinafter each such push button will be identified by the referencecharacter U preceded by a number corresponding to the floor at which thebutton is located. In a similar manner, FIG. 1 shows a down push button21) which may be operated by a person desiring to travel in the downdirection. A similar push button would be located at each floor fromwhich a person may desire transportation in the down direction.

In order to signal the approach and direction of an elevator car toprospective passenger, suitable floor signals such as lanterns may beprovided. Thus, in H6. 1, an up lloor lantern ZLAU and a down floorlantern ZLAD re illustrated. Similar lanterns may be provided at eachfloor requiring such signals.

As the elevator car approaches a floor at which it is to stop, it isdesired that the car stop automatically and accurately in registrationwith the floor. To this end, position-responsive mechanism is providedin the hoistway and on the elevator car. Thus, FIG. 1 shows anelectromagnetic unit EU mounted on a bracket 22 which is secured to theelevator car. A separate inductor plate or vans P constructed ofmagnetic material such as steel is located in the hoistway for each ofthe floors served by the car. When the car is accurately stopped at adoor, the unit EU is associated with the plate P for such floor in themanner illustrated in FIG. 1. For further details of construction of theunit EU and the plate P, reference may be made to the aforesaid OplingerPatent 2,874,806. The application of the unit EU will be discussedfurther in connection with FIGS. 12 and 13 below.

Further control of the operation of the elevator car is provided by adoor selector 23 (FIG. 1) which conveniently may be mounted on thepenthouse floor 3. his floor selector is supplied with two drive inputs.One is a drive input by an advance motor AM located on the top of thedoor selector. A second drive input is supplied for the purpose ofdriving the floor selector in accordance with movement of the elevatorcar. Such a drive input may be provided in any desired manner. Forexample, a drive tape may be provided in a known manner for mechanicallydriving the selector unit in accordance with movement of the elecatorcar. However, in FIG. 1, a preferred drive of the self-synchronous typeis provided. Such a drive includes a transmitter or generator SG whichis connected electrically to a receiver or motor SM. The transmitter orgenerator SG is coupled to the secondary sheave 9 or the traction sheave5 through suitable gearing 25. A self-synchronous drive of this typetogether with a suitable advance drive are described in detail in theSavage Patent 2,657,765.

FLOOR SELECTOR The floor selector is illustrated in greater detail inFIGS. 2 through 11. Referring first to FIGS. 2 and 3, it will be notedthat a plurality of angles 27 and other structural parts are associatedin any suitable manner to provide a rigid framework or supportingstructure 29.

As previously pointed out, two drive inputs are supplied to the doorselector. One of the drive inputs is supplied by the advance motor AM,which is mounted on top of the door selector supporting structure 29 andwhich drives a sprocket Wheel 31 through a slip coupling. The motor SMalso is mounted on top of the supporting structure 29 and drives asprocket wheel 33 through a releasable coupling. These slip andreleasable couplings are {fully described in the aforesaid Savagepatent. It will be noted that the sprocket wheels 31 and 33 are parallelto each other and are mounted for rotation about parallel axes.

The supporting structure also supports two spaced parallel guideelements or rails 35 and 3'7, which are employed in part for guiding twocarriage units 43 and 45,

5. respectively. The rails 35 and 37 may be fabricated of a suitablematerial such as aluminum which is extruded to have the desired uniformcross section to be described below.

Certain control operations are performed by the carriage units 43 and4-5 as the elevator car moves in its hoistway. When the car is to bebrought to a stop at a desired floor, the carriage units also arebrought to a stop at predetermined points corresponding to the desiredfloor. In order to perform the desired operations, a plurality offloor-stop units are provided. Certain of the floor-stop units aresecured to the rail 37 and are employed primarily during down travel ofthe elevator car. These units will be designated by the referencecharacter FSD preceded by the number of the floor corresponding to thestop unit. Thus, the reference character 91 i) designates the stop unitfor the ninth floor associated with the rail 37". Although stop unitsare shown only for the first and ninth floors in FIGS. 2 and 3, it willbe understood that similar stop units will be provided between theillustrated stop units for the intermediate floors. The stop unitsassociated with the rail are employed primarily for up travel of theelevator car and will be designated by the reference character FSUpreceded by the number of the floor corresponding to the stop unit. Itis to be understood, however, that certain parts of the carriage unitsand 45 move in unison, and the floor-stop units associated with therails 35 and 37 may be employed for certain functions during travel ofthe elevator car in either direction.

Each of the floor-stop units associated with the guide rail includes afirst set of pileup switches 49, a second st of pile-up switches iii, athird set or" pile-up switches 49A, a fourth set of pi e-up switches HAand clamping means for securing these switches to the associated guiderail. Each of the floor-stop units also includes a lug which undercertain conditions may be employed for stopping the associated carriageunit when a stop is to be made at the associated floor by the elevatorcar. In additicn, each floor-stop unit has a cam for operating a set ofpile-up switches secured to the carriage unit 43. he construction of thefloor-stop units will be discussed in greater detail below. in a similarmanner, each of the floor-stop units associated with the guide rail 3?includes a set of pile-up switches 53, a set or" pile-up switches 55, aset of pile-up switches 53A, a set of pile-up switches 555A, at lugwhich under certain conditions is utilized for stepping the associatedcarriage unit do when the elevator car is to p at the associated floorand a cam for operating a set or pileup switches secured to the carriageunit 45.

The carriage unit 43 is divided into two main parts comprising asynchronous carriage 43S and an advance or lead carriage 43A. in ananalogous manner, the carriage unit includes a synchronous carriage andan advance carriage 45A.

The synchronous carriages 43S and 455 are moved in opposite directionsin accordance with movement of the associated elevator car. in thepreferred embodiment of the invention illust .ted in the drawings, thesynchronous carriages 43S and are connected in a flexible loop by meansof flexible members such as chains 56 and 57. The chain as has its endsconnected respectively to the upper ends of the synchronous carriagesand passes around the sprocket wheel .33, which is driven by thesynchronous motor SM, and an idler sprocket wheel 56A. The ends of thechain 57 respectively are connected to the lower ends of the synchronouscarriages, and this chain passes around a pair of idler sprocket wheels559A and By inspection of FIGS. 2 and 3, it will be observed that thesynchronous carriages are driven in ogposite directions by the motor SMin accordance with movement of the associated elevator car.

The advance carriages 43A and 45A similarly are associated for movementin opposite directions by means of chains all and The chain 61 has itsends connected to E5 the upper ends of the advance carriages and passesaround the sprocket wheel 31, which is driven by the advance motor AM,and an idler sprocket wheel 61A. The chain 63 has its ends connected tothe lower ends of the advance carriages and passes around a pair ofidler sprocket wheels 65A (not shown) and 65B.

The advance carriages are connected to the synchronous carriages bymeans of a lost-motion coupling. Consequently, they move in unison withthe synchronous carriages except for such relative movement as ispermitted by the lost-motion coupling. The advance motor under ertainconditions may move the advance carriages relative to the synchronouscarriages by the distance permitted by the lost motion coupling.

The advance carriage 43A carries an up pawl relay hich operates a set ofpile-up switches 67. As hereinafter pointed out, energization of thecoil of the relay also projects a stop pawl into a position to engagethe lug of one of the floor-stop units during up travel of the elevatorcar, and such energization also projects a cam into position foroperating certain of the switches carried by one of the doorstep units.in addition, the advance carriage 43A carries switches (one of which lSUis illustrated FIGS. 2 and 3) which are operated in response to relativemovement of the advance and synchronous carriages 43A and 438. Theconstruction of these various parts w ll be discussed in greater detailbelow.

in an analogous manner, the advance carriage 45A carries a down pawlrelay DPL which operates a set of pile-up switches es. Energization ofthe coil of this relay also projects a pawl into position to engage thelug of one of the associated floor-stop units during down travel of theelevator car, and projects a cam into position to engage certain of thepile-up switches carried by one of the floor-stop units. In addition,the advance carriage id/l carries switches (one of which i) isillustrated in FIGS. 2 and 3) which are operated in response to relativemovement of the advance and synchronous carriages 45A and 45S.

inasmuch as connections must be made between switches mounted on theadvance carriages and external circuits, a pair of flexible cables "illand 73 are provided. Each of the conductors in the cable 71 has an endconnected to an. appropriate switch mounted on the advance carriage d3'3. Certain of the conductors also are connected to the coil of therelay UPL. The remaining ends of the conductors are connected toexternal circuits, as desired. Sufilcient play is provided to permit theflexible cable Fl to follow or trail the advance carriage 43A withoutinterfering with the motion thereof. The cable '73 similarly isassociated with the advance carriage it may be pointed out that thecarriage unit 43 is erfestive for stopping the elevator car only whilethe carriage unit is traveling in an up direction. The parts are soarranged that the carriage unit 45 also is effective for a stoppingoperation only while traveling in the up direc- =tion. For this reason,the floor-stop units iFSU and llFSD are located at opposite ends of thefloor selector.

The present selector also includes two solenoid control units UM andDial, which are employed for controlling deceleration, and, if desired,acceleration of the elevator car. The solenoid control unit UM includesa coil UMC, which is mounted on the advance carriage 43A, and a softmagnetic armature UMA, which is mounted on the synchronous carriage 433of the selector. Consequently, relative movement of the advance andsynchronous carriagcs results in movement of the armature UMA relativeto the coil UMC for the purpose of varying the impedance thereof. asimilar manner, the solenoid control unit BM includes a coil DMC, whichis mounted on the advance carriage 45A, and :a soft magnetic armatureDMA is mounted on the synchronous carriage 45S. Relative movement of thecarriages 45A and 458 results in variation in the impedance of the unitDM. The units 6 UM and DM will be described in greater detailhereinafter.

Referring more particularly to the FIGS. 4 and 6, it will be noted thatthe advance carriage 43 includes a body in the form of a rigid plate 75,which may be fabricated of steel and which is spaced from and extendsparallel to the rail 35. Spaced from the plate 75 and mounted on therear of the plate near the right edge thereof, as viewed in FIG. 4, forrotation relative thereto about vertically-spaced parallel axestransverse to the plate are an upper roller 76 and a lower roller 77.Preferably, the axes of the rollers 76 and 77 are spaced equally from ahorizontal centerline of the plate 75. These rollers are disposed totravel in a longitudinal groove '78 formed in the right side of the rail35. Spaced from the plate 75' and mounted adjacent the left edge thereofon a block 79 for rotation relative thereto about an axis parallel tothe axes of the rollers 76 and 77 is a roller 80. This roller isdisposed to travel in a longitudinal groove 81 formed in the left sideof the rai' Thus, the grooves '78 and $1 provide tracks for guita -1 theadvance carriage 43 accurately along the guide r 35. The rollers 76, '77and 8% may be fabricated of any suitable material such as rubber orpolyurethar The block 79 extends through a notch 82 in the plate 75 andis mounted for rotation about a vertically-extending pin 33 which passesthrough an aperture in the block and whose ends which are reduced indiameter, extend into respective apertures in a pair of posts 34 and 85.The posts 84 and 35, in turn, are mounted by suitable means on the frontside of the plate 75.

As is shown clearly in FIGS. 4 through 7, the up pawl relay UPL has asoft magnetic core 86, which is secured to a frame 87. The frame may beconstructed of a soft magnetic material such as soft iron or steel, andthe coil of the relay surrounds the magnetic core. The frame 37 issecured to the advance carriage plate '75. The relay UPL includes a softmagnetic armature 88, which is illustrated in FIGS. 4, 6 and 7 in itsenergized or picked up condition and in FIG. in its deenergized ordropped out condition. The armature 88 is mounted on the frame 87 forrotation about a pin 89, the pin extending through apertures in thearmature and in the frame and the plate 75. It will be noted that thearmature 88 carries a cam arm 90 which is positioned to operate the setof pile-up switches 67.

The set of pile-up switches 67 is of conventional construction andincludes a plurality of parallel electroconductive leaf springs 91 and$2, which carry contacts insulated from each other and which are biasedto predetermined positions. ln the specific embodiment of FIG. 4, theset of pile-up switches includes two sets of break contacts, which areopen when the relay is in its energized or picked up condition. inaddition, the set includes three sets of contacts of the make type,which engage each other when the relay is in the energized or picked upcondition shown in FIGS. 4 and 6. However, any other arrangement ofcontacts may be employed if so desired. It will be noted that the set ofpile-up switches includes a cam follower 93 which is positioned forengagement by the cam arm W. The cam follower is biased toward the left,as viewed in FIG. 4, by means of a leaf spring 4. Consequently, when therelay is deenergized, the cam follower 93 moves to the left in order topermit return of the sets of contacts to the positions they occupy whenthe relay is deenergized. Insulating spacers 95 position the leafsprings $1 and 9 2 for the desired relationships of the contacts carriedthereby. An insulating strip $6 has suitable apertures for receiving theend of one leaf spring 94 in order to transmit motion from the camfollower i to the various contact leaf springs.

The armature 8d of the up pawl relay UPL also has a cam 7 securedthereto. Conveniently, the cam 94 is extended to form the cam 97. Whenthe up pawl as relay is in its energized or picked up condition, the cam97 is positioned to engage certain switches mounted on the floor-stopunits. When the relay is in its deenergized condition, as is shown inPEG. 5, the cam d7 clears all of these switches.

Referring to FIGS. 6, 7 and 10, the armature 38 also has an arm 95 whichcarries a stop pawl 99. When the relay UPL is in its energized or pickedup condition, the stop pawl 99 is positioned to engage a stop lug on thenext one of the floor-stop units reached by the pawl. In FIG. 7, thestop pawl 99 is positioned in engagement with the lug 1% carried by theclamp of the floor-stop unit S FSU. It will be noted in FIGS. 4 and 5that the advance carriage plate has a notch lill through which the arm93 extends and which provides clearance sufiicient to permit substantialmovement of the arm without interference by the plate when the up pawlrelay is deenergized or dropped out. An adjustment screw le is inthreaded engagement with the cam arm as and when the relay UPL isdeenergized, engages the inner wall of the notch fill to determine theposition of the armature 38. The screw liiii is retained securely in itsadjusted position by means of locking nut 11%.

it will be noted that the advance carriage has at its upper and lowerends adjustable sockets 1M and 105, which are in threaded engagementwith respective brackets 1% and 197 secured to the plate '75". Thesesockets receive the ends of the chains 61 and 63, which are securedthereby to the advance carriage, as is shown in FIG. 6.

By reference to FIGS. 7 and 9, it will be noted that the movable cam 97is positioned to operate the sets of pileup switches 4-9 atpredetermined points in the travel of the elevator car, provided the uppawl relay UPL is energized. An additional cam lt fi is secured to theadvance carriage plate 75. This cam is positioned to engage the set ofpile-up switches 51 mounted on each floor-stop unit during travel of theelevator car. Since this cam is fixed to the advance carriage, it isalways in position to engage these switches at predetermined points inthe travel of the car.

Two additional fixed cams T169 and ill (FIGS. 4, 7 and 9) are secured tothe left side of the plate 75 of the advance carriage 43. These cams arepositioned to cooperate respectively with the sets of pile-up switches4JA and 51A during travel of the elevator car.

The construction of the sets of pile-up switches as, 51, @A and 51A inFIGS. 7 and 9 will be understood from the description of the set 67 inFIG. 4. It will be apparent that in each set make and break contacts maybe provided, as required. It also will be understood that the point ofoperation and the duration of operation of each of the sets of pile-upcontacts may be determined by the position and length of the associatedcam.

It will be observed that the sets of pile-up contacts 49, 531., and 51Afor each of the floor-stop units are secured to the clamp 112 for thesame floor by means of cars 1135 which project from the clamp body. Asis shown, certain of the sets such as the sets 49 and 49A may bepositioned slightly below the other sets 51 and 51A and may be slightlystaggered with respect thereto.

Referring now to FIGS. 4, 7 and 10, the advance carriage plate 7d alsohas secured thereto a set of pile-up switches 115, Whose construction issimilar to that of the sets heretofore discussed. The set Ill-5 has acam follower 117, which is positioned to engage a earn 119 on the nextone of the floor-stop units reached by the cam follower. In FIG. 7, thecam follower lll7 is positioned in engagement with the cam Ell carriedby the clamp 112 of the floor-stop unit SK SU. By reference to FIG. 10,it will be noted that the cam H9 is designated to engage the camfollower ll? and thus to operate the set of pile-up switches llfi inboth directions of travel of the carriage unit 43.

clamo lllZ (FIGS. 7, 9 and 1G) is generally t3- shaped and has two legs1312A and 1123. The rail 35 has a shoulder or flange 12?. which isengaged by the clamp leg 112A and a shoulder or flange 123 which isengaged by the leg 112B. It will be noted that a groove or notch 125 isformed in the rail adjacent the shoulder 121. The legs and the shouldersare proportioned so that the leg 1124A may be inserted into the notch125 around the shoulder 121, after which the clamp H2 may be rotatedsuiiiciently to pass the leg 1123 around the outer end of the shoulder112-3. Then the clamp may be moved to the left, as viewed in PKG. 7, toassume the position illustrated. To remove the clamp from the rail, theforegoing sequence is reversed.

For adjustably securing the clamp M2 to the associated rail, the clampadditionally includes a web 127 which has an oblique cylindrical portion129. The portion 129 has an aperture 131, which is threaded to receivein the rear end thereof a screw 133. The body portion of a plunger rssalso is inserted into the aperture 131 through the front end thereof.Thus, the screw 133- may be adjusted to determine the length of the bodyportion of the plunger which is received in the aperture 131.

it will be observed that the rail 35 has a longitudinallyextending rearoblique surface 13?, which faces the external end surface of the plunger135. Consequently, the clamp 112 may be adjusted along the guide rail35, and the screw ll3l3 thereafter may be rotated to locate the clampaccurately in any desired position of adjustment; i.e., as the screw 133is tightened, the plunger 135 and the oblique rail surface 137 cooperateto draw the clamp legs lllZA and 1123 tightly against the shoulders 121iand 123, respectively, with the end of the leg 112B engaging the sidesurface of the rail 35 adjacent the shoulder m3, as is clearly shown inFIG. 7. A nut 3 9 is provided for locking the screw 133 in position toprevent loosening of the clamp 112 after the screw is tightened. Sincethe same guide rail is employed for uiding the advance carriage 4?, itis apparent that proper alignment between the various parts is assuredand that a slight camber or twist of the rail will not affect theiroperation.

By inspection of FlGS. 4, 6, 7 and 8, it will be noted that a switchplate Ml is secured to the advance carriage plate 75 by means of threespacers 145. A screw 145 secures the plate 141 to the frame 87 of the uppawl relay UPL. The switch plate Ml is parallel to the advance carriageplate 75 and has formed therein a plurality of longitudinally-extendingslots 147. Because of its appearance, the plate Mil conveniently may bereferred to as a cage plate.

The slots i i; are employed for adjustably positioning a plurality ofcage switches, such as the switches 1311 and ZSU. Each switch bodybridges its associated slot and has an operating plunger 149 formed ofinsulating material such as phenolic resin. An end of the plunger i i-9extends through such slot to form a cam follower h. Each switch may besecured to the plate 141 by any suitable means, such as a screw 15]. anda nut 153, the latter of which also is sufhciently large to bridge theassociated slot. Consequently, each switch may be adjusted in a verticalpath to the proper position, and the screw lldl then may be tightened toclamp the switch securely to the plate 141 and thus to the advancecarriage 43A.

As is clearly shown in H6. 6, each of the cage switches includes a topplate 15:3 and a bottom plate 157. Disposed between these plates areplurality of insulating spacers 15d and a pair of leaf springs 16?. and163, each of which carries a contact. The top and bottom plates, theinsulating spacers and the leaf springs are secured together by means ofa screw lldd and a nut 165'. The screws 151 and are insulated from theleaf springs ltill and 163 by any suitable means such as by insulatingtubing (not shown) surrounding the respective screw bodies.

The plunger lllil has a first shoulder positioned against the bottomplate 157. Extending from this shoulder and through an aperture in thebottom plate 157 and one of the slots in the cage plate M2 is a pin-likeprojection which forms the aforementioned cam follower 156. The plungerl4?! also has a second shoulder l6? spaced from the shoulder 65.Extending from the shoulder it?! is a pin-like projection T169, which isinserted through an aperture in the top plate Surrounding the plungerprojection 1659 between the shoulder in? and the top plate 155 is ahelical spring l-fil which biases the plunger toward the right to theposition shown in PEG. 6.

It will be observed that the spacing between the plunger shoulders 16b"and 167 provides a peripheral groove 173 in the plunger and that theleaf spring 163 extends into this groove. Thus, movement of the plungerM9 toward the left, as viewed in FIG. 6, results in movement of the leafspring 163 in the same direction to close the switch contacts. While theswitch ESU is illustrated as of the make type, i.e., one whose contactsare normally open, it will be apparent that reversal of the respectivepositions of the leaf springs lll and will result in a switch of thebreak type, that is, one whose contacts are normally closed and areopened by movement of the switch plunger against the biasing of thehelical spring Although live cage switches are illustrated in MG. 7, itwill be understood that additional switches, as desired, may be securedto the cage plate ltdll to operate in a similar manner.

The cage plate Ml also carries a suitable clamp for securing theflexible electrical cable '71 to the carriage unit 43. As isillustrated, this clamp may take the form of a pair of parallel barsT75, between which are disposed similarly shaped pieces of insulatingmaterial such as felt 177. The bars and the insulating material aremounted on spacers 1'79, and the cable 71 is retained securely betweenthe forrner components by means of screws llll.

Referring again to H65. 4 and 6, it will be observed that thesynchronous carriage 438 includes a body in the form of a rigid plate1526 which may be fabricated of steel. The plate 183 is disposedbetween, spaced from and parallel to the advance carriage plate and thecage plate 141.

Spaced from the advance carriage plate 75 and mounted on the front ofthe plate adjacent the left-hand edge thereof, as viewed in FIG. 4, forrotation relative thereto about vertically spaced axes transverse to theplate are an upper roller and a lower roller 137. Preferably, the axesof these rollers are spaced equally from the horizontal centerline ofthe plate 75. Spaced from the plate 75 and mounted adjacent theright-hand edge thereof on a block 139 for rotation relative theretoabout an axis parallel to the axes of the rollers 185 and 187 is aroller 191. Each of the rollers 185, lid? and i911 has a peripheralgroove 185G, T376 and l'lG, respectively, for receiving and guiding thesynchronous carriage plate 183. Consequently, the advance carriageguides the synchronous carriage 43$ for movement in a direction parallelto the rail 35'. Conveniently, the rollers 1&5, 31557 and R91 ray beconstructed of material having relatively low friction such as nylon.

As is illustrated in detail in FlG. ll, the roller block 189 extendsthrough a notch H3 in the advance carriage plate 75 and is mounted forrotation about a pin which extends through an aperture in the block andwhose ends which are reduced in diameter, pass into respective aperturesin a pair of posts 197 and 199. These posts, in turn, are mounted by anysuitable on the rear of the plate 7 '5.

Turning again to FIGS. 4- and 6, a bolt Edi extends through apertures inthe advance carriage roller block 7 9 and the synchronous carriageroller block 139. Compressed between each block and the adjacent end ofthe bolt Zhl are separate respective compression springs 7% and 1898.Consequently, the spring 793 biases the advance carriage roller 8% intoits groove or track ill and thus the advance carriage rollers '76 and*7" into their groove or track '78 so that the rollers firmly grasp therail 35. Similarly, the spring 1398 biases the synchronous carriagerollers 185, 127 and 191 firmly against the synchronous carriage plateThis arrangement assures that the advance and synchronous carriages areguided accurately in their desired paths.

The axis of rotation of the left-hand advance carriage roller Stlpreferably extends transversely of a line drawn therefrom and parallelto the horizontal centerline of the advance carriage plate '75 to a lineextending between the axes of rotation of the right-hand advancecarriage rollers 7s and 77 and parallel to the plate 75. Likewise, theaxis of rotation of the right-hand synchronous carriage roller 191extends transversely or a line drawn therefrom and parallel to thehorizontal centerline of the plate '7 to a line extending between theaxes of rotation of the left-hand synchronous carriage rollers 185 andl87 and parallel to the plate '75. in the illustrated embodiment of theinvention, the axes of rotation of the rollers 3t) and 191 intersect thehorizontal ccuterline of the advance carriage plate 75' in order toprovide balanced forces between the rollers '76 and 77 and the rail andbetween the rollers 135 and 187 and the synchronous carriage plate 183.By virtue of the construction described, the advance carriage 43A alwaysis located in the same general position relative to the rail 35 eventhough the rail may be cambered or twisted, and the synchronous carriage43S always is located in the same general position relative to theadvance carriage altnough the carriage plates may be somewhat warped.

The synchronous carriage plate 183 also has adjustable sockets 2% andfor reception respectively of the ends of the chains 56 and 57 (H6. 6),which are secured thereto. The sockets have adjustable screws, which arein threaded engagement with respective brackets 29S and 266 secured tothe synchronous carria e plate, and may be adjusted, as required.

As is clearly shown in FIGS. 4, 6 and 8, the synchronous carriage plate133 has secured thereto a cam 2h? which is designed to operate thevarious switches, such as the switches llSU, ZSU, etc., which aresecured to the cage plate 141. It will be observed that the switches areoperated by engagement of the cam with the cam followers 159 in responseto relative movement between the advance and synchronous carriages. Aspreviously pointed out, the position at which each switch is operatedmay be adjusted by adjusting the position of the desired switch relativeto the advance carriage.

An advance stop 20% (FIGS. 6 and 8) is secured to the cage plate 14-1and may be adiusted along one of the slots l l'i thereof for the purposeof adiusting the magnitude of the lost-motion coupling between theadvance and synchronous carriages. This stop is proportioned to engagethe lower end of the synchronous carriage cam 2W7, thus determining theamount of movement in one direction of the advance carriage relative toits associated synchrous carriage.

The soft magnetic armature UMA of the solenoid control unit UM (FIGS.4-, 6, 7 and 8) comprises a plurality of laminatious located within thecoil UMC when the elevator car is positioned accurately at a floor toprovide maximum impedance of the coil. The armature UMA is secured tothe synchronous carriage plate 183 by means of a lamination supportmember 211, which is constructed of a non-magnetic and a non-conductivematerial such as a phenolic resin, and a pair of brackets 213. Thearmature and coil may be configured to provide any desired pattern ofvariation of impedance of the coil in response to relative movement ofthe coil and its armature. For present purposes, it will be assumed thatthe impedance of the coil varies in a linear manner with such relativemotion.

The coil UMC is contained within a tube 214, and the coil and the tubeare mounted on the advance carriage plate by means of a pair of endplates and a pair of brackets 2:17. The end plates 215 are secured toeach other for holding the tube 2% and the coil UMC firmly in place bymeans of a pair of tie rods 21?. in order to provide a low-reluctancemagnetic path for ilux produced by the coil, its tube and end plates areconstructed of a soft magnetic material such as steel. For someapplications the lower end plate may be of a nonmagnetic material suchas brass. Each of the end plates has a slot 221 extending from theperiphery to the inner opening thereof and the tube 214 has a slot 223extending lengthwise thereof and aligned with the slots 221 forpreventing the establishment of a shorted turn around the coil UMCthrough its mounting components.

Frovision is made for resetting the synchronous carriage each time astop is made by the elevator car. "t will be recalled that for each stopthe advance carriage is positioned accurately by the associatedfloor-stop unit, and the elevator car is positioned accurately undercontrol of the electromagnetic unit EU and the associated inductor plateP (FIG. 1). To facilitate the resetting of the synchronous carriage, thesynchronous carriage is provided with a structure having one or morenotches. As is shown in FIGS. 4- and 6, this structure may take the formof a plate or centering cam 231 mounted on the synchronous carriageplate 133. The earn 231 has a pair of oppositely disposed cam notchesand 235 for receiving a pair of rollers 237 and 239, respectively. Theserollers are mounted for rotation about their respective axes at the endsof arms 237A and 239A, and the arms, in turn, are pivotally mounted onthe advance carriage plate 75 by means of pins 237? and 2355?.

A bolt 241 extends through the arms 237A and 239 Compressed between eacharm and the adjacent end of the bolt 241 are separate respectivecompression springs 2378 and 235-8. These springs bias the rollers 237and 239 into the notches 233 and 235, respectively. Consequently, if thesynchronous carriage is free to move relative to the advance carriageand is displaced slightly from the position illustrated in FIG. 4, therollers will force the synchronous carriage into the correct position.The bias is insufiicicnt to interfere with movement of the advancecarriage relative to the synchronous carriage by the advance motor.

It is believed that construction of the carriage unit 45 and each of thefloor-stop units FSD will be clear from the foregoing description of thecarriage unit 43 and the floor-stop unit @FSU. The parts associated withthe rail 37 in FIGS. 2 and 3 are substantially identical to the partsassociated with the rail 35. The advance carriage 45A is guided relativeto the rail 37 in substantially the same manner by which the advancecarriage 43A is guided by the rail 35. The down pawl relay DPL operatessubstantially in the same manner as the up pawl relay UPL. When the downpawl relay DPL is energized, it operat s the pile-up switches 69 bymeans of a cam arm 959K win h corresponds to the cam arm 9d associatedwith the up pawl relay UPL. in addition, the down pawl relay positions amovable cam 97X to engage certain pile-up switches 53 associated withone of the fioor-stop units. Additional camps MEX, ltli x and llllX aresecured to the advance carriage 45A to operate pile-up switches 51, 43Aand 51A, respectively, in substantially the same mannor by which thecams 1th and ill. associated with the advance carriage 43A operateswitches. Each par associated with the carriage unit 45 which correspondto a related part associated with the carriage unit 431 is identificd bythe same reference character followed by the sullix X.

When the down pawl relay DEE is energized, it positions a stop pawl 9Xto engage a lug ZltlhX of a floorstop unit during upward travel of thecarriage unit This corresponds to the operation of the stop pawl 99 andthe lug 1%. It will be understood that a clamp MEX amazes s a it is foreach of the floor-stop units .FSD is associated with the rail 37, andthe sets of pile-up switches 53, 55, 53A and EiSA. are securedto theclamps lllZX in substantially the same manner discussed for thefloor-stop unit QPSU. Furthermore, each of the clamps Ill-X has a cam119K which operates a set of pile-up switches MEX mounted on the advancecarriage 45A. These components respectively correspond to the cam H9carried by the clamp 112 or he floor-stop unit 9FSU and the set ofpile-up switches lit; secured to the advance carriage 43A.

Switches, such as a switch liSD, correspond to the switches, such as theswitch ISU, of the up carriage unit, and are secured to a cage plate MIXin the same manner. These switches are operated by a cam ZiWX in thesame manner by which the switches of the up carriage unit 43 areoperated by the correspondin cam 26 7. The synchronous carriage isguided by the advance carriage MA in a manner which will be clear fromthe discussion of the corresponding parts of the carriage unit Althoughthe positions and lengths of the various cams may be selected inaccordance with the requirements of each elevator system, it may behelpful to consider a specific example. Dimensions or displacements willbe given in terms of feet of car travel corresponding to thedisplacements of the advance carriages from the positions they occupywhen the elevator car is steppe at a floor. Thus, the earns 97 and @/'X(when in canming position) may operate the switches 49 and 525 two feetbefore the floor and release the switches one foot after the floor. Thecams 1th; and l'iltiX may opcrate the switches 51 and 55 two feet beforethe floor and may release the switches four feet after the floor. Thecam 169 may operate the switches 49A four feet before the floor and mayrelease the switches four feet after the floor. The cam Lltll X mayoperate the switches 53A six feet before the floor and release theswitches six feet after the floor. The cams ill. and 111K may operatethe switches 51A and 55A four feet before the floor and may release theswitches two feet after the floor. Finally, the doorstep unit earns 119and 119K may operate the advance carriage switches 115' and 115K onefoot before the floor and may release the switches one foot after thefloor.

ELEVATOR CGNTROL SYSTEM As previously pointed out, the invention may beernployed with various types of elevator control systems. In order toillustrate the application of the invention to a suitable elevatorcontrol system, reference will be made to the circuits shown in FIGS. 12and 13, which: as has been noted, are based respectively on FIGS. 4A and4- of the OplingerPatcnt 2,874,806. In these circuits a number ofelectromagnetic relays and switches are illustrated. These relays andswitches may have contacts of the make type, which are closed when therelay or switch is energized or picked up and which are opened when therelay is deenergized or dropped out. Alternatively, the relays orswitches may have break contacts, which open when the relay or switch isenergized or piclzed up and which are closed when the relay or switch isdeenergized or dropped out. Each of the relays and switches will bedesignated by a suitable reference character, and each set of contactswill be designated by an appropriate suffix in the form of a numeral.For example, the expression U1 designates the first set of contacts forthe up switch U, whereas the expression U3 designates the third set ofcontacts for the up switch U.

In order to facilitate consideration of the control system, thefollowing components of FIG. 12, the circuits of which are shown indeenergized condition, are illustrated which or identical with and/orserve functions El, E2, ill-a, B2a Direct-curent buses.

til Door relay. UPB

Up push button. Down push button. Door closing relay. Up switch.

Down switch.

Car running relay.

219, etc Down floor call push button.

2BR, etc. Down floor call registering relays.

ZDRN, etc. Down floor call canceling coils.

AD, etc,

etc. EUR, etc.

Down lanterns.

Up floor call push buttons.

Up floor call registering relays.

Up lloor call canceling coils.

EURN, etc.

ponents, reference may so made to the aforesaid Oplingcr patent. Inaddition to these components, the pr sent 12 includes the following newcomponents:

51 Pile-up switches of floor-stop units.

Floor call above relay.

Pile-up switch of advance carriage 43A.

In order to ascertain whether a iloor call exists for a floor above heposition of the elevator car, a floor call above circuit is provided.This circuits includes in series breal: contacts for all of the up anddown floor call registering relays arranged in order of the lloors. Toconserve space, call above circuit contacts for the sixth, seventh andeighth floors are omitted in Fi'G. 12.

The floor call above circuit 232 includes pile-up switches of the llOOlstop units associated with the floor selector carriage unit Thus, theswitch )i is in the doorstop unit for ...rst iioor, and tie switch5.163% is in floor-stop unit for the second floor, etc. Each of thepileup switches 5l(l)lr through 51(99-11 is connected to the floor callabove circuit in such a way that all floor call registering relays re aring travel of the elevator car above the liner represented by a p'le-upswitch are located above such switch. For example, the contacts lUR3 and5BR are contacts of floor call registering relays which require travelof the elevator above the fourth floor, but not above the fifth floor.Consequently, these contacts are located in the floor call above circuit232 between the pile-up switches 5'.l(-t-)l and 5I.()l.. The pile-upswitches 5l(6)l, l(7)-l and 5l(il)l are not illustrated in FIG. 12, butit will be understood that they are associated with the circuit in asimilar manner. (The pile-up switch l is connected directly to the bus1, since it is assumed that the ninth floor is the highest floor servedby the elevator car.)

As has been po nted out in the preceding discussion of the present'floorselector, in terms of feet of car travel corresponding to thedisplacement of the advance carriage 43A from the position it occupieswhen the elevator car is stopped at a floor, each of the switches51(1)-1 through l(9)1 is closed by the cam N8 two feet before thecorresponding floor and is opened by such cam four feet after suchfloor. Consequently, as long as no floor call is registered requiringtravel of the elevator car above its position, no set of break contactsin the floor call above circuit 232 is open which may effectdeenergization of the floor call above relay 78U.

It also will be recalled that in terms of feet of car travelcorresponding to the displacement of the advance carriage 43A from theposition it occupies when the elevator car is stopped at a floor, itspile-up switch 1Il51 is opened by each of the floor-stop unit cams 131%one foot before the corresponding fioor and is closed by such cam onefoot after such floor. if the pile-up switcl 154 is closed when thefloor call above relay 8U is picked up, closure of make contacts "willestablishes a self-holding circuit for the relay. Energizat'ion of therelay 7$U also is accompanied by opening of its break contacts 78U2 todeenergize the lamp 233, thus indicating that no floor call isregistered for a floor above the position of the elevator car.Conversely, dropout of the relay 73U results in opening of make contacts'78U1 to interrupt the selfiholding circuit for the relay and in closureof break contacts T'tlUZ to energize the lamp 233, thus indicating theregistration of a floor call for a floor above the position of theelevator car. Conveniently, the lamp 233 may be located within theelevator car for observation by the car attendant.

As has been indicated, the present FIG. 3 is based on FIG. 4A of theaforesaid Oplinger patent. Consequently, reference may be made theretofor a complete understanding of the components of FIG. 13. To facilitateconsideration of FIG. 13, the following components thereof are listedwhich are identical with components bearing the same referencecharacters in the aforesaid Oplinger patent:

1 Elevator car motor. MA Motor armature. MP Motor field.

G Generator. GA Generator armature. GPl, GFZ Generator field windings.GRl, GRZ Generator field resistors. ltl Control unit. PM Pattern motor.PM PMZ, Z27 Pattern motor windings. 215 Pattern motor lever. 231Electroconductive disc. 237 Permanent magnet. 239, 241 Rheostats. 24 7,255 Generator field transformers. 257 Generator anti-hunt winding. UM Upsolenoid control unit. DM Down solenoid control unit. 259 Solenoidcontrol unit transformer. 2-63 Voltage regulator. (30 BR Auxiliary breakrelay. EU Electromagnetic unit. P Magnetic plate.

It will be recalled that a number of switches are operated in accordancewith relative movement between the floor selector advance andsynchronous carriages. Suitable conditions of operation of theseswitches for the specific system under consideration are illustrated inFIG. 14. However, it should be understood that the lead of the advancecarriages relative to the synchronous carriages and the operations ofthe various switches may be selected in accordance with the requirementsof each elevator system. In FIG. 14, the reference line corresponds to aposition of the advance carriages in registration with the synchronouscarriages. Such registration occurs when the elevator car is stopped ata floor. Ordinates above and below the reference line indicate the leadof the advance carriages relative to the synchronous carriagesrespectively for up travel and down travel, as the elevator car nearsthe floor at which it is to stop. By inspection of FIG. 4, it will benoted that the maximum lead in either direction is of the order oftwenty feet (expressed in terms of the corresponding feet of cartravel). As was discussed heretofore (FIGS. 6 and 8), such lead for theadvance carriage 43A may be determined by adjustment of the advancecarriage stop 269 along its associated slot 147 of the cage plate 141,and similarly for the advance carriage 45A. Returning to FIG. 14, linesare illustrated therein to indicate the period during which switcheshave their contacts closed. For example, the switch 151] is positionedto have its contacts closed from a position wherein the elevator car isapproximately one foot above each floor to a position wherein thecarriage 43A has its full lead or advance for travel in a downwarddirection. These contacts are open when the advance carriage is 10V6d inthe up direction by more than a foot (expressed in terms of acorresponding foot of car travel) from the position which it occupieswhen the elevator car is stopped at a floor. As a further example, theswitches MSU and 118i) are closed when the elevator car is withinapproximately twenty inches of a floor at which it is to stop for eitherdirection of travel. These switches are open when the advance carriagesare moved in either direction by more than twenty inches (expressed interms of corresponding inches of car travel) from the position theyoccupy when the elevator car is stopped at a floor. It is believed thatthe operating conditions for the remaining switches can be ascertainedby reference to FIG. 14.

OPERATION A. Car M'oves From F irst Floor to Fourth Floor It is believedthat an understanding of the invention will be facilitated by adiscussion of certain typical operating sequences for the elevatorsystem. For the first sequence, it will be assumed that the elevator car11 (FIG. 1) is parked at the lower terminal or first door in a positionof registry therewith, that the car gate 21 and the hoistway door 19 areopen and that a passenger desiring to proceed to the fourth floor entersthe elevator car. It further will be assumed that the direct-currentbuses B1, B2, Bil-a and B2-a (FIGS. 12 and 13) are energized.

While the elevator car is parked at the lower terminal floor with itsdoors open, the transfer relay TR (FIG. 12) is energized. Also, the coil193 is energized. As is explained in the aforesaid Oplinger and Savagepatents, this coil, when energized, effects the resetting of thesynchronous carriages 43S and 45S relative to the advance carriages 43Aand 45A (FIGS. 2 and 3). In addition, the down pawl relay DPL (FIG. 12)is energized through its holding contacts DPLl and break contacts DCZ.Finally, the floor call above relay '78U is energized and picked upthrough the pile-up switch contacts 5ll(1)-1 and the serially connectedbreak contacts of all of the floor call registering relays in thecontrol system. Closure of make contacts 73U1 has no immediate effectson operation, inasmuch as the pile-up switch contacts -1 in seriestherewith are open. Opening of break contacts 78U2 effect deenergizationof the lamp 233, thus indicating to the elevator car attendant that nofloor call is registered in the system. All other electromagnetic relaysand switches in FIGS. 12. and 13 are deencrgized at this time.

When the passenger enters the elevator car, the attendant operates thecar call push button 4C to register a car call for the fourth floor. Asis explained in the aforesaid Oplinger patent, the car call push buttonsare of the type which when actuated by the car attendant remain actuateduntil the elevator car reverses its direction of travel; and althoughthe resetting of these push buttons may be performed automatically, itis assumed that they are reset manually by the car attendant after thecompletion of each trip in one direction.

Next, the elevator car attendant operates the up push button UPB toenergize the door closing relay DC. This relay, when energized,initiates closure of the hoist-way door for the lower terminal floor andthe car gate in a conventional manner. As a result of such closures, thedoor relay 4% is energized. This relay closes its make contacts 49-2,40-3, 40-4 and 40-5 to prepare certain circuits for subsequentenergization. In addition, break contacts 40-6 open to deenergize thecoil 193. As a result of such deenergization, the sprocket wheel 33(FIGS. 2 and 3) is coupled to the synchronous motor SM, and freemovement of the synchronous carriages 43S and 458 is prevented.

When the door closing relay DC was energized, it opened its breakcontacts DC1 and DCZ. Opening of the contacts DCl has no immediateefiiect on operation. Opening of the contacts DCZ results indeenergization of the down pawl relay DPL. The operation of the up pushbutton UPB also results in completion of the following circuit followingclosure of make contacts 49-1:

B1, UPB, 46-1, U, ISD, 32, 132-12 The switch ISD is positioned to haveits contacts closed from a position wherein the elevator car isapproximately one foot below a stop to a position wherein the selectoradvance carriages are fully advanced for car travel in an upwarddirection.

Energization of the up switch U results in closure of its make contactsU1 and U2 (FIG. 13) to connect the coil PMl of the pattern motor PM tothe rectifier 261 for energization in the proper direciton for up travelof the elevator car when the contacts TRZ and TR3 close. Make contactsU3 (FIG. 12) close to prepare a holding circuit for the switch U and thecar running relay 32 for subsequent completion. Make contacts U4 closeto repare the up pawl relay UPL for energization as the elevator carapproaches a door for which an up floor call is registered. Finally,make contacts U6 and U7 close to complete an energizing circuit for theadvance motor AM. The direction of energization of the advance motor, asdetermined by the contacts U6 and U7, is correct for up travel of theelevator car.

At this stage, a substantial part of the resistor R2 is shunted, and thearmature of the advance motor is energized through the circuit:

Bl-a, 40-5, 7SU, 'I'SD, DPIA, UPL4, U6, AM, U7, B2

By reference to FIGS. 2 and 3, it will be recalled that the advancemotor AM rapidly moves the advance carriage 43A in an upward directionthrough the distance permitted by the lost-motion coupling between theadvance and synchronous carriages. The relative motion of the advancedand synchronous carriages results in movement of the armature UMA awayfrom the up solenoid control unit coil UM.

As the advance carriages are moved by the advance motor relative to thesynchronous carriages, the switch 1SU opens. By reference to FIG. 12, itwill be noted that such opening prevents energization of the down switchD. Movement of the advance carriage 43A also results in disengagement ofthe cam follower 117 (FIG-S. 7 and 10) of the pile-up switch 115 fromthe cam 119 of the floorstop unit lFSU. Consequently, the contacts 115-1(FIG. 12) close to complete the holding circuit of the floor call aboverelay 78U. Further movement of the advance carriage effects opening ofthe switch 4SU to prevent energization of the coil 193. Next, the camfollower of the pile-up switch 51 associated with the floor-stop unitfor the first floor (refer to FIGS. 7 and 9) disengages the advancecarriage cam 1G8, and the contacts 51(1)-1 (FIG.

18 12) thus open. However, energization of the relay 'iSU is maintainedthrough its holding circuit.

As the advance carriage continues to move, the switch SSU closes topermit energization of the up pawl relay UPL by a registered car call.However, for reasons which will be set forth below, such energizationcannot take place until the advance carriage nears a positioncorresponding to a floor for which a car call is registered.

Continued movement of the advance carriage 43A results in movement ofthe armature UMA (FIGS. 2. and 3) out of the associated solenoid coilUMC to provide minimum impedance of the coil. For present purposes, itwill be assumed that the characteristics of the control system are suchthat suitable acceleration of the elevator car is obtained if thesolenoid coil UMC has minimum impedance.

During movement of the advance carriages, the switch ilSU opens todeenergize the transfer relay TR. This occurs when the movement of theadvance carriages is equivalent to twenty inches of car travel. Inaddition, this switch 7SU opens as the advance carriages near theirfully advanced positions to introduce a substantial portion of theresistor R2 in circuit with the armature of the advance motor AM. Thisreduces heating of the advance motor, but sufiicient torque is producedby the advance motor under these conditions to force the advancecarriages to follow the synchronous carriage movements.

Upon dropout, the transfer relay TR closed its break contacts TRZ andTR3 (FIG. 13), and opened its make contacts TR4 and TRS to place thecoil PM]. and the relay BR through the contacts U1 and U2 under controlof the up solenoid control unit UM. Additionally, break contacts TRl(FIG. 12) closed to complete a holding circuit for the car running relay32 and the up switch U which may be traced as follows:

B1, TRI, 4-0-2, U3, U, ISD, 32, BZ-a Consequently, the car attendant nowmay release his up push button UPB. Such release deenergizes the doorclosing relay DC, which closes its break contacts DCI and DCZ. Theclosure of these contacts has no immediate etfect on system operation.

It will be assumed that the advance carriage 43A now is fully advancedand that the stop 209 (FIGS. 6 and 8) is in engagement with the cam 20'?of the synchronous carriage 435. From this point on, the advancecarriages can advance only with the associated synchronous carriages.

If desired, the elevator system may be designed so that the elevator carstarts to move before the advance carriages reach their fully advancedpositions. However, in a preferred embodiment of the invention, theadvance carriages are moved rapidly and reach their fully advancedpositions before the elevator car starts to move.

It will be recalled that the car running relay 32 was energized at thetime the up switch U was energized. As a result of its energization, thecar running relay closed its make contacts 32-1 (FIG. 13) to release theelevator car brake. Such release permits upward travel of the elevatorcar. The car running relay when energized also closed its make contacts32-2 and 32-3 (FIG. 12) to prepare holding circuits for the pawl relaysUPL and DPL for subsequent operation.

Inasmuch as break contacts TR2 and TR3 (FIG. 13) and make contacts U1and U2 are closed, the winding PMl of the pattern motor PM and theauxiliary brake relay BR are connected across the secondary winding ofthe transformer 259 through the rectifier 261 and the coil UMC of the upsolenoid control unit UM. Since the coil UMC now has minimum impedance,maximum energization is applied to the winding PMl of the pattern motor,and the resultant torque applied to the lever 215 decreases materiallythe effective resistance of the rheostat 241. The decreased resistanceof the rheostat is 241 results in the flow of substantial currentthrough the primary winding of the transformer 255, and the generator Gconsequently is excited for full speed operation in the up direction.The energization of the generator field windings GF1 and SP2 isaccompanied by the inducing of voltage in the winding 257 to energizethe winding PMZ of the pattern motor PM. The develops a force acting inopposition to the force produced by energization of the winding Pit i1.However, the energization of the winding PMZ exists only while theenergization of the field windings is changing. The purpose of thewinding PM2 is to decrease hunting of the motor 1.

The motor 1 now accelerates to move the elevator car in the updirection. Such acceleration is accompanied by acceleration of the disk231, which is coupled electromagnetically to the lever 215 through themagnet 237. As the speed of the motor increases, the torque applied tothe lever 215 by the disk 231 increases until a condition of equilibriumis reached, at which time the speed of the motor corresponds to thedesired running speed of the elevator car. Any deviation of the elevatorcar from the desired speed results in a change in the torque applied tothe lever 215 by the disk 241. This change is in the proper direction torestore the motor 1 to the desired speed.

As the elevator car moves, car motion is transmitted through thetransmitter or generator SG (FIG. 1) to the motor SM. This motorthereupon drives the synchronous carriages 43S and 45S (FIGS. 2 and 3)in accordance with car movement. Since the advance carriages 43A and 45Anow are biased by the advance motor AM in the direction of travel of thesynchronous carriages, it follows that all of the carriages move as aunit.

As the elevator car approaches each floor, the floorstop unit pile-upswitch 51 associated with such floor is operated to close its contactsin the circuit of the floor call above relay 78U, and, within one footof the floor, the advance carriage pile-up switch 115-1 in the holdingcircuit of the relay is opened as explained heretofore. Consequently, ifa fioor call is registered for a floor above, the floor call above relay78U drops out to close its break contacts '78U2, thus energizing thelamp 233. However, it is assumed that no floor call is registered in thesystem at the present time, and thus the relay 78U remains picked up.

It will be assumed that one of the switches in each of the sets 49A(FIGS. 2, 7 and 9) is employed for picking up a car call for theassociated floor in either direction of travel of the elevator car.Thus, in FIG. 12, the switch 49A(1)-1 is in the floor-stop unit for thefirst floor, the switch 49A(2)-1 is in the floor-stop unit for thesecond floor, etc. However, the closure of one of these switches iseifective for a control operation only if the associated car call pushbutton is in operated condition.

As the elevator car approaches the fourth floor and advance carriage 43Anears its fourth-floor position, the switch 49A(4)-1 for the fourthfloor is closed. This closure may take place when the advance carriageis short of the position which it occupies when the elevator car is atthe fouith floor by a distance of the order of four feet measured interms of car travel. Since it is assumed that the advance carriage leadsthe elevator car by a distance equivalent to twenty feet of car travel,it follows that the switch 49A(4)1 is closed when the elevator car isapproximately twenty-four feet from the fourth floor. Upon closure ofthe switch 49A(4)1, the following circuit is completed:

B1a, 4C, 49A(4)1, 419-4, 3511, UPL, B2

Upon energization, the up pawl relay UPL moves the cam arm 1i: (FIGS. 4and 6) to operate its contacts represented by the set of pile-upswitches 67. Each one of the switches will be identified by thereference character UPL followed by an appropriate suffix. As is shownin FIG. 12, closure of make contacts UPL1 completes a 2Q holding circuitfor the up pawl relay through make contacts 32-2. Opening of breakcontacts UPL3 and UPL4 introduces substantial resistance in series withthe advance motor AM shortly before the advance carriages are brought toa stop. This reduces heating of the advance motor as the elevator car isbrought to a stop.

The energization of the up pawl relay UPL also projects the cam 97(FIGS. 7 and 9) into position for operating the set of pile-up switches49 for the fourth floor. The expression 4 101? designates the set forthe fourth floor. One of these switches 49(4)-1 (FIG. 12) is closed bythe cam to energize the canceling coil dURN for the fourth floor in theevent that an up floor call is registered for the fourth floor. However,under the assumed conditions, no floor call has been registered. The camalso closes contacts 49(40-2 for the purpose of energizing the uplantern LAU for the fourth floor.

In addition, energization of the up pawl relay UPL results in projectionof the stop pawl 99 (FIGS. 7 and 10) into position to engage the lug 1%associated with the clamp 112 of the floor-stop unit associated with thefourth floor. Consequently, as the advance carriage 43A continues itsupward travel, the pawl W engages the lug 1% for the floor-stop unit ofthe fourth floor to bring the advance carriages to a stop.

As the elevator car continues in the upward direction, the synchronouscarriage 43S (FIGS. 4, 6 and 7) moves with respect to the advancecarriage 43A to operate the switch 1SU and similar switches mounted onthe advance carriage. As previously explained, these switches areoperated in accordance with the development illustrated in FIG. 14.

Movement of the synchronous carriage 43S (FIGS. 2 and 3) relative to theadvance carriage 43A also results in movement of the armature UMA towardthe coil UMC of the up solenoid control unit UM. The movement of thearmature is accompanied by a gradual increase in the impedance of thecoil UMC and consequently by a gradual decrease in the energization ofthe winding PM1 (FIG. 13) of the pattern motor PM. The resultantreduction in the torque applied to the lever 215 by the pattern motorresults in movement of the lever in a clockwise direction about itspivot 217 to increase the effective resistance of the rheostat 241. Thisdecreases the current supplied to the primary winding of the transformer255 and thereby the excitation of the generator G. Since the excitationchanges, a voltage is induced in the winding 257 which is in a properdirection for minimizing hunting of the motor 1.

When the elevator car reaches a distance of the order of twenty inchesfrom the fourth floor, the switches TISU and 1181) (FIG. 12) close tocomplete an energizing circuit for the transfer relay TR. This relayopens its break contacts TR1 to interrupt the holding circuit for the upswitch U and the car running relay 32. The transfer relay also opens itsbreak contacts TR2 and TR3 (FIG. 13) to disconnect the coil of the upsolenoid control unit UM from the winding PM1 and the auxiliary brakerelay BR. Make contacts "PR4 and TRS close to connect the winding PM1and the relay BR for energization under control of the electromagneticunit EU.

Deenergization of the up switch U is accompanied by opening of its makecontacts U1 and U2 (FIG. 13) and U3 and U4 (FIG. 12) without immediateeffect on the operation of the system. Opening of make contacts U6 andU7 deenergizes the advance motor AM. Drop-out of the car running relay32 is accompanied by the open ing of its make contacts 32-1 (FIG. 13).However, make contacts BB1 of the auxiliary brake relay BR close beforethe brake can drop out. ()pening of make contacts 32-2 and 323 (FIG. 12)has no immediate effect on the operatie-n of the system.

At the time the transfer is made, the electromagnetic. unit EU (FIG. 1)is adjacent the lower end of the plate P for the fourth floor which hasa substantial. shielding ef-- 11 fect. Consequently, a larger current isprovided by the rectifier 271 (FIG. 13) than by the rectifier 267, andthe winding Phil of the pattern motor PM is energized with properpolarity to continue the upward motion of the elevator car at a low rateof speed.

As the elevator car continues its upward motion, the current applied bythe rectifier 271 decreases and the current supplied by the rectifier267 increases to decrease the difference therebetween. This graduallyreduces the energization of the winding PMl and consequently reduces thespeed of the elevator car. When the car reaches a position of registrywith the fourth floor, the voltage applied to the winding PM is reducedto zero, and the elevator car speed is zero. Consequently, the car is atrest accurately at the desired floor. At this stage, the voltage appliedto the auxiliary brake relay BR also reduces to zero, and this relayopens it make contacts BRl to permit application of the brake 7. Shouldthe elevator car be displaced from the fourth floor thereafter for anyreason such as cable contraction or stretch, the car will be returnedinto registry with the floor by a sequence which will be understood fromthe aforesaid Oplinger patent 2,874,806.

After the elevator car arrives at the fourth floor, the car attendantopens his car gate and the hoistway door for the fourth floor in orderto discharge his passenger. As a result of such openings, the door relay(FIG. 12) is deenergized. This relay opens its make contacts 43-1,ill-2, 46%, 4tl4 and 40-5, but such openings have no resent eifect onthe operation of the system. The relay also closes its break contacts40-6 to complete an energizing circuit for the coil 193.

It will be recalled that energization of the coil 193 uncouples thesprocket wheel 33 (FIGS. 2 and 3) from the motor SM. Since the sprocketwheel no longer prevents free movement of the synchronous carriages, therollers 237 and 239 (FIGS. 4 and 6) can effect movement of thesynchronous carriages into exact registration with the advance carriagesin the event that resetting is necessary.

It also will be recalled that when the elevator car is stopped at thefourth floor, the advance carriage cam Hi8 (FIGS. 7 and 9) is inengagement with the cam follower of the set of pile-up switches 51associated with the floorstop unit for the fourth floor. In addition,the floor-stop unit cam 1?.9 (FIG-S. 7 and 10) is in engagement with thecam follower 117 of the set of advance carriage pileup switches 1.15.Consequently, the contacts 51(d)1 (FIG. 12) in the energizing circuit ofthe floor call above relay itlU are closed, and the relay is energizedand picked up. Thus, break contacts '78U2 are open to effect continueddeenergization of the lamp 233, indicating to the elevator car attendantthat no floor call is registered for a floor above the fourth floor. Inaddition, the contacts lid-ll in the holding circuit of the relay 78Uare open. Should break contacts 51316, for example, open as the resultof the registration of a down floor call for the fifth floor, the relay7811 would drop out to close the contacts "itlUZ, and the lamp 233,therefore, would be energized to indicate the registration of a floorcall for a fioor above the fourth floor.

B. Car Moves From Fourth Floor to Second Floor Next, it will be assumedthat the elevator car is positioned at the fourth floor during a downtrip. The down pawl relay DlL is assumed to have been energized to bringthe car to a stop at the fourth floor, and the down lantern for thefourth floor is illuminated. At this time, a prospective passenger onthe second floor operates the push button 213 for the second floor inorder to register a down floor call. By reference to FIG. 12, it will benoted that operation of the push button 2D energizes the down floor callregistering relay ZDR. This relay closes its contacts ZDRL to establisha holding circuit for itself. In addition, the relay closes its makecontacts ZDRZ to prepare for subsequent energization therethrough of thedown pawl .22 relay DPL. Cpening of break contacts 2DR3 has no immediateeffect on operation, since these contacts are below the closed pile-upswitch contacts Eil(d)l in the energizing circuit of the floor callabove relay ESU.

The car attendant now operates the down push button DPB to energize thedoor closing relay DC. This initiates closure of the hoistway door forthe fourth floor and the car gate. The door closing relay also opens itsbreak con tacts D01 and DCZ. In opening, the contacts DCZ deenergize thedown pawl relay DPL, and this relay thereupon opens contacts 53(4)-2(corresponding to contacts 53(2-)-2. for the second floor) to interruptthe illumination of the down lantern for the fourth floor. The openingof the contacts 53(4)1 (corresponding to contacts 53(2)1 for the secondfloor) has no immediate efiect. The down pawl relay DPL also opens itscontacts DPLI, but this has no immediate effect on the system. Breakcontacts DPLS and DNA close to permit shunting of substantial parts ofthe resistor R2.

Closure of the car gate and the hoistway door energizes the door relayid. This relay closes its make contacts 404;, ill-2, id-4 and 4tt-5, butsuch closures have no immediate efiect on the operation of the system.in addition, the door relay opens its break contacts 46-6 to deenergizethe coil 193 in order to permit the motor SM (PEGS. 2 and 3) to drivethe synchronous carriages 43S and ass.

The operation of the down push button DPB (FIG. 12) by the elevator carattendant also completes the following circuit after closure of makecontacts 40-3:

B1, DPB, lli-3, D, llSU, 32, Bil-a The resulting energization of thedown switch D closes make contacts D1 and D2 (FIG. 13) to prepare thecoil Phil of the pattern motor PM for energization in the properdirection for down travel of the elevator car. Closure of make contactsD3 and D4 (FIG. 12) has no immediate eifect on system operation. Closureof make contacts D6 and D7 completes an energizing circuit for theadvance motor AM, the direction of energization being correct for downtravel of the elevator car. Since the resistor R2 is shunted, theadvance motor rapidly advances the associated advance carriages.

As the advance carriages are moved relative to their associatedsynchronous carriages, the switch lSD opens to prevent energization ofthe up switch U. The switch 38D closes to permit energization of thedown pawl relay Dl-L when the elevator car is to answer a registered carcall. The switch 48D opens to prevent encrgization of the coil 193during down travel of the elevator car. The switch 73D opens tointroduce resistance in series with the armature of the advance motorshortly before the advance carriages reach their maximum advance for thedown direction. Finally, the switch llSD opens to denergize the transferrelay TR, and this relay closes its break contacts TRl, TRZ and TR3(FIG. 13) and opens its make contacts TR4 and TRS.

The car running relay 32 upon being energized closes its make contacts324. to permit release of the elevator brake. Closure of make contacts32-2 (PIG. l2) has no effect on operation, while make contacts 32-3:close to prepare a holding circuit for the down pawl relay DPL forsubsequent operation.

it will be recalled that the advance carriages reach their maximumadvances prior to movement of the elevator car. The advance of thecarriage 45A (FIGS. 2 and 3) is accompanied by movement of the armatureDMA away from the coil DMC of the down solenoid control unit DM toreduce the impedance of the coil. Consequently, a substantial current issupplied to the winding PMl (FIG. 13) of the pattern motor PM from thesecondary winding of the transformer 259 through the low impedance ofthe coil DMC, the rectifier 262, make contacts D1 and D2 and breakcontacts TRZ and TR3. The auxiliary brake relay BR also is energized andpicked up. The current to the pattern motor has the proper polarity toproduce downward motion of the elevator car. Thus, the pattern motorapplies a torque to the lever 21$ acting in a clockwise direction aboutthe pivot 217. The resulting movement of the lever 215 operates thesprings 239A through 2.39? to reduce the effective resistance of therheostat 239. This permits substantial current to flow through theprimary winding of the transformer 247, and the transformer suppliesthrough the rectifier 253 direct current to the field windings GFIl andGEL. of the generator G with proper polarity for down movement of theelevator car.

As the motor 1 accelerates, it rotates the disc 2.31 to apply throughthe magnet 237 a torque to the lever 215' which acts in opposition tothe torque applied by the winding PMI. An equilibrium finally is reachedwhen the elevator car operates at the desired speed. As previouslynoted, the winding 257 operates to minimize hunting of the system.

As the elevator car moves in the down direction, the generator ortransmitter SG (FIG. 1) energizes the motor SM to drive the synchronouscarriages 43S and 4:38 (FIGS. 2 and 3) in synchronism with movement ofthe elevator car. Since the advance carriages 43A and 45A. aremaintained in their advance positions, they move in unison with thesynchronous carriages during full speed travel of the car in the downdirection.

Registered down floor calls are picked up by one of the pile-up switchesin each of the floor-stop unit sets 55A (FIG. 2). As the advancecarriage 45A approaches each of the associated floor-stop units insuccession, it operates successively the sets of switches 55A. When theadvance carriage reaches a predetermined point, such as a position whichmay be four feet (measured in terms of car travel) before the secondfloor, it closes the switch 55A(2)l (FIG. 12). This is one of theswitches of the set 55A associated with the floor-stop unit for thesecond floor. Since the advance carriage leads the elevator car by adistance of twenty feet (measured in terms of car travel), it followsthat the switch 55A(2)-l is closed when the elevator car is abouttwenty-four feet from the second floor.

Upon closure of the switch 55A(2)l, the down pawl relay DPL is energizedthrough the following circuits:

Bil-a, 55A(2)ll, ZDRZ, D4, DPL, B2

The down pawl relay closes its make contacts DPLI to establish throughthe now closed make contacts 32-3 a self-holding circuit. In addition,break contacts DPL3 and DPL4 open to insert additional resistance inseries with the advance motor AM shortly before the advance carriagesare brought to a stop.

It will be recalled that the down pawl relay DEL upon energizationprojects its cam 97X into position to engage the set of pile-up switches53 for the second floor (see the corresponding components 97 and 49,FIGS. 7 and 9). By reference to FIG. 12, it will be observed that theset of switches 5'3 for the second floor includes a switch 53(2)l, whichis closed to energize the canceling coil ZDRN. Such energization cancelsthe down floor call registered for the second floor. In addition, asecond switch of the set, 53(2)-2, closes to energize the down floorlantern ZLAD for the second floor. Deenergization and drop-out of thedown floor call registering relay 2BR has no immediate efiect on theoperation of the system.

The energization of the down pawl relay DPL also resulted in theprojection of the pawl 99X into position to engage the lug llti't Xassociated with the clamp HEX for the floor-stop unit associated withthe second floor (see the corresponding components 99, 1%, and 112, H63.7 and 1(1). Consequently, the pawl 99X engages the associated lug tobring the advance carriages to a stop when the elevator car isapproximately twenty feet from the second iloor. Continued movement ofthe elevator car results in movement of the synchronous car- 2d riagesrelative to the advance carriages. It will be recalled that suchrelative motion operates a plurality of cage switches mounted on theadvance carriage 45A (FIGS. 2 and 3), for example, the switch lSD.

The relative motion of the carriages also moves the armature DMA towardthe coil DMC to increase the impedance or" the coil gradually. Theincrease in impedance of the coil results in a gradual decrease incurrent supplied to the winding PMIl (FIG. 13) of the pattern inotor PM.The resultant movement of the lever 215 in a counterclockwise directionabout its pivot 217 increases the effective resistance of the rheostatand consequently reduces the excitation of the generator G. As a result,the elevator car is slowed gradually as it at preaches the second floor.

When the car reaches a distance of the order of twenty inches from thesecond floor, the switches 113D and lllSU (FIG. 12) close to energizethe transfer relay TR. This relay opens its break contacts TRl tointerrupt the holding circuit for the down switch D and the car runningrelay 3 2. In addition, break contacts TR2 and TR3 (FIG. 13) open tointerrupt the energization of the winding PMl through the coil DMC.Closure of make contacts T124 and TR5 connects the winding PMl and theauxiliary brake relay BR for energization under control of theelectromagnetic unit EU.

The down switch D in dropping out opens its make contacts D1, D2 (FIG.13), D3 and D4 (FIG. 12) without immediately effecting the operation ofthe system. Opening of make contacts D6 and D7 results in deenergizationof the armature of the advance motor AM. Dropout of the car runningrelay 3?. is accompanied by opening of its make contacts 32ll (FIG. 13),but the closure of make contacts BRl of the auxiliary brake relay BRprevents application of the brake '7. Opening of make contacts 32-2 and32-3 (FIG. 12) has no immediate etfect on system operation.

When the transfer occurs, the electromagnetic unit EU (FIG. 1) isadjacent the upper end of the plate P for the second floor. In thisposition of the elevator car, the plate has little shielding action onthe electromagnetic unit. Consequently, the rectifier 267 (FIG. 13)sup-plies substantial current whereas the rectifier 271 supplies asmaller current to the resistor 273. The resultant voltage across theresistor energizes the winding PMl of the pattern motor PM with properpolarity for continued down travel of the elevator car. As the carcontinues its approach to the second floor, the plate P applies anincreasing shielding action, and the voltage applied to the winding PM!consequently decreases gradually. This means that the speed of theelevator car also is decreased gradually until the car reaches aposition of registration with the second floor. At this point, thevoltage across the resistor 273 is reduced to zero, and the speed of theelevator car also is reduced to zero. The auxiliary brake relay BR dropsout to open its make contacts BRl, thus permitting application of thebrake 7. The elevator car is retained accurately in registry with thesecond hour. Should the car be displaced from the second floor for anyreason such as cable contraction or stretch, the electromagnetic unit EUwould initiate return of the car into registry with the second floor, aswill be understood by reference to the aforesaid Oplinger Patent2,874,806.

During the final movement of the elevator car, the switch 48D (FIG. 12)closed (such closure may occur when the car is two feet from the secondfloor). Such closure prepares the coil 1% for subsequent energization.In addition, the switch 183) closed when the elevator car was within onefoot of the second floor to prepare the up switch U for subsequentenergization.

The elevator car attendant now opens his car gate and the hoistway doorfor the second floor to receive the waiting passenger. Such openingsresult in deenergization of the door relay 4%. Opening of make contacts40-1, M 1, 4045, 449-4 and dii-S has no immediate effect on system

1. IN A FLOOR SELECTOR FOR CONTROLLING OPERATION OF AN ELEVATOR CARSERVING A PLURALITY OF FLOORS OF A BUILDING STRUCTURE, A CARRIAGE, ASUPPORTING STRUCTURE HAVING ONLY A SINGLE GUIDE RAIL FOR GUIDING SAIDCARRIAGE ALONG A PREDETERMINED PATH, A PLURALITY OF FLOOR UNITS SPACEDIN THE DIRECTION OF SAID PATH AND SECURED TO SAID RAIL, ROLLER MEANSMOUNTING SAID CARRIAGE ON SAID RAIL FOR MOVEMENT RELATIVE TO SAIDSUPPORTING STRUCTURE ALONG SAID PATH, SAID ROLLER MEANS COMPRISING AFIRST AND A SECOND ROLLER SPACED IN THE DIRECTION OF SAID PATH ANDENGAGING A FIRST SIDE OF SAID RAIL, SAID ROLLER MEANS ALSO INCLUDING ATHIRD ROLLER ENGAGING A SECOND SIDE OF SAID RAIL OPPOSITE SAID FIRSTSIDE, MEANS MOUNTING SAID FIRST, SECOND AND THIRD ROLLERS ON SAIDCARRIAGE FOR ROTATION RELATIVE TO SAID CARRIAGE AND TO SAID RAIL ABOUTSPACED PARALLEL RESPECTIVE FIRST, SECOND AND THIRD AXES, SAID THIRD AXISBEING DISPOSED ON A FIRST LINE DRAWN FROM SAID THIRD AXIS TO A SECONDLINE TRANSVERSE TO SAID FIRST LINE AND EXTENDING BETWEEN AND TRANSVERSETO SAID FIRST AND SECOND AXES, MEANS BIASING SAID THIRD ROLLER TOWARDSAID FIRST AND SECOND ROLLERS, AND TRANSLATING MEANS HAVING A FIRSTCOMPONENT ON EACH OF SAID FLOOR UNITS AND A SECOND COMPONENT ON SAIDCARRIAGE, SAID TRANSLATING MEANS BEING RESPONSIVE UNDER PREDETERMINEDCONDITIONS TO A PREDETERMINED POSITION OF SAID CARRIAGE RELATIVE TO EACHOF SAID FLOOR UNITS.